[Survivor 69/Z28]

This is what I did to my 69 Z, maybe an idea for you.

My car has some old school headers. So we ran 2.5 all the way to a flowmaster crossflow muffler. Then we ran 2.5 from the crossflow to the factory style tail pipes. The entire system was set up with the factory hangers.
It looks very stock, but of course flows much better than one of the resto exhaust system and sounds awesome.

For performance you would of course want to use 2.5 tailpipes.